But how do you know whether you might trigger a pet peeve or whether you forgot some crucial detail?

We tapped four creative agencies on your behalf and asked them for the critical must-haves and thou-shalt-nots for would-be designers and creative developers. Here are words of wisdom from execs at AKQA, JESS3, Code & Theory and Mekanism — heed them well, and add your own tips in the comments section.

5 Mistakes to Avoid from JESS3

Jesse Thomas founded creative agency JESS3. His firm has done great work for tons of tech brands such as Google, Facebook and Wikipedia; JESS3's also worked for mainstream consumer brands, including Nike. He gives us a quick run-down of five things not to do when applying for a job.

Don't misspell anything. "This is the cardinal sin of sending a resume to anyone," Thomas says. "Run spell check, and if you really can't spell with spell check a click away, then you should perhaps go back to school."

Always include a cover letter. "You should write a very personal and direct note that explains the key things you want explained ... This is the test of your professional tone," he says.

Use a professional email address that is some variation of your actual name, and make sure your name is listed in your email account — got it, cre8tivedude97@hotmail.com? "Obviously we all have had emails and chat names that we wouldn't want others outside of our social circles to see," says Thomas, "but if you send me an email that doesn't have the name set up and it just shows me a Hotmail address in the name field, you suck at email."

Use a professional tone. Thomas makes the salient point, "I need you to be writing my company's emails, so if you can't impress me with yours, why would I want to hire you?"

Never send a prospective employer an email from your mobile. "It's a rookie, noob move and you know it!" Thomas says.

3 Quick Tips from Code & Theory

Brandon Ralph is a partner and executive creative director at New York-based firm Code & Theory, which was recently charged with redesigning Vogue's website. He gives the following words of advice to would-be designers:

Your first email should include a short and sweet subject line that introduces you and names the position you're applying for. Why the simplicity? "It's good to stand out," says Ralph, "but don't be so clever that it comes off as arrogant."

Always include a PDF version of your resume. Ralph says, "Layout matters, but so does scannability."

Give your prospective employer a link to your portfolio website, then "let the work speak for itself," says Ralph. "A cumbersome interface sometimes gets in the way of the work."

7 Dos and Don'ts from AKQA

AKQA is one of the leading interactive-focused agencies in the country. Two of the firm's creative recruiters, Lionel Carreon and Barbara Tejada, share these three things they love in candidates — and four red flags.

Aim for the following:

Your portfolio should be filled with home runs. "Your work should challenge us, take us out of our comfort zone and make us jealous."

Make sure you can give an elevator pitch for each of your pieces. "Be prepared to speak about your work from brief to completion and explain your ideas simply."

Do your homework, kids. Tejada and Carreon say you'll need to "know everything about the agency you are applying to."

Try to avoid these faux pas:

Now is not the time to be bashful about communication. "Call and email the places you want to work for, but do it within reason," they say.

Don't bad-mouth past experiences, including "ex-clients, ex-agencies, ex-colleagues or that bad cup of coffee you had earlier."

Discouragement and pessimism are the enemy in your job search. "Don't give up," the AKQA team says. "If an agency passes on your work, work someplace else and prove them wrong."

And finally, Carreon and Tejada caution applicants to avoid using the third person in cover letters and resumes. "It’s just creepy."

10 Pointers from Mekanism

Finally, we hear from a few staffers at Mekanism, one of the most creative firms in the world of digital storytelling. Brendan Gahan is the firm's social media director. He, a Mekanism copywriter, a PR staffer and the firm's president, Jason Harris, relay the following tips to would-be creatives:

Be passionate about wanting to work at that specific firm. "Be fans of the work," said Gahan. "This is more than a job."

Be a self-starter. Gahan says he looks for candidates who, "even if they haven't had a ton of work experience, are already creating stuff on their own."

Of course, it helps to have an "amazing work ethic," Gahan says. And if someone can vouch for you on this point, all the better.

It goes without saying that you'll need "a website highlighting your work," and Gahan also points out ...

One of the firm's PR folks says that you can stand out in a positive way simply "by having a point of view and a personality. ... Don't be afraid to be witty or edgy — just avoid being offensive."

And here's a word for newer or younger applicants: "Be bold, especially if you're a new college graduate. It's challenging landing your first internship or gig out of school, so don't be afraid to cold call or email people you respect within the industry for informational interviews."

Express your passions, such as music or fashion, even if they're not necessarily related to the job description. The PR person says, "There are brands out there that can benefit from insights you may have from your other interests. And if you have connections in media in any specific verticals, let your dream employer know."

Finally, the firm's president gives the following practical and political tip: "Learn the [agency's] creative work up and down, point out your three favorite pieces of work, and say why they're your favorites. Flattery gets you everywhere."

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Every week we put out a list of social media and web job opportunities. While we post a huge range of job listings, we've selected some of the top social media job opportunities from the past two weeks to get you started. Happy hunting!

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